In push-pull assemblies where connections exist between a core element and a control member it is desirable to provide some kind of insulator or isolator to insulate the core element from the control member. This is particularly true in a gear shift assembly where the core element controls a control member which vibrates due to its connection to a transmission. Ideally, the isolator will absorb all of the vibration from the control member so that no vibration travels along the core element to the gear shifter. U.S. Pat. No. 4,327,600 to Bennett discloses a terminal having a socket member and an isolator for dampening vibration; but the isolator is only an "O" ring disposed between the control element and the socket member. It is still possible in such an arrangement for vibration to be transmitted from the control element to the terminal via the socket member. U.S. Pat. No. 4,581,953 to Walston et al. discloses a terminal having a socket member which is soft enough to serve as an isolator. But the relatively soft socket member does not have the retaining power of a harder, more rigid socket member. Nor does this arrangement provide the flexibility of allowing the socket member and the isolator to be inserted or replaced independently of one another. This flexibility can be important not only in the maintenance of the assembly, but also in allowing the assembly to be adapted for different applications.